In general, a wafer may be processed in various types of processing tools. Therefore, the wafer may be positioned in the processing tool via a wafer chuck. Various types of wafer chucks may be already know. However, a conventionally used wafer chuck may be designed to contact a backside of a wafer physically, wherein a main processing surface, also referred to as a front side, of the wafer faces away from the wafer chuck. In the processing tool, the front side of the wafer may be processed as desired. The processing via the processing tool may include a processing in a plasma, wherein the wafer chuck may be configured as an electrode to apply a bias voltage and/or a voltage for generating the plasma.